Trick the check panel for brake light?

[MA-BMW]

My check panel says I have a brake light out. Which I have confirmed I do not. Is there a way I can trick the check panel into thinking they are all working? Well, they are all working but that's not the point. It gets annoying when I start driving and when I tap the brakes the Check light flashes on the dash. Thanks.

[Bimmerista]

You eventually have to tap on the brakes. Just don't do it immediately.

[Motorsports]

I've had three E30 and they've all done this. It is annoying after a while.

[StereoInstaller1]

Wanna fix that shit forever? READ and FOLLOW these instructions EXACTLY, and your issue will go away for years. Takes about 15 minutes total, if you have the stuff on hand.

Here is what to do first: Go buy a can of CRC "Electrical Contact Cleaner" and perhaps a couple of Q tips, and a nice new pencil eraser. Maybe have a bit of sctochbrite and some of the red shit you spray on your battery to prevent corrosion (I don't use that shit, BMW didn't) if you want to see if that stuff makes your connections stay good more than 15 years.

Now, Find the "rear lights check relay", it is a small black box, about 3" X 2" X 4" with a few wires coming off its ass end. It is under the same panel as the antenna and the amplifier, AKA left trunk liner. Unbolt it and BOTH taillights, unplug all 3 and place them on a workbench or something, or piss off Mom and use the kitchen table.

Now, take a close look at the connectors in the car. Spray them heavily with CRC. Use Qtips, scotchbrite, whatever the hell you ave to scrub the connections down in the plug...then spray again...get them all nice and shiny clean. I think I used a toothbrush on mine.

Cleaning the rear lights check relay is really simple, just scrub the contacts with a pencil eraser, then douche with CRC. They clean up aesily.

Now, on to your taillights. Take the backing off of the lense, and if you want to "never deal with this stupid check panel light again" (like me) pull the bulbs out one at a time, and scrub the holes with Scotchbrite and CRC, until the bastards look NEW. Make sure you clean the point where the ground is attached, too...that one plate grounds the whole plate, make it perfect.

Now, reassemble car, with or without new bulbs...clean the bulbs if you are reusing them, though. While reassembling, make sure you are using the correct bulbs (NOT 1157s). Check to make sure every single connection is nice and tight. You can use a metal pick tool (which every single person on this board should own) to pull the connections tighter...whatever...just make sure every single connection is tight.

Your "CHECK" light should light up every time you turn the key on. As soon as you step on the brakes, that CHECK light should turn off, unless there are other issues.

Now, go do a thorough job cleaning this crap and be happy!

Luke

[Tavern Gnome]

Seriously Luke, you are the MAN!! I'm going to give it a whirl.

[StereoInstaller1]

Easy fix, has worked on 3 E30s for me, 100% flawless.

When I joined R3V, there was a bunch of discussion about needing to use certain types of light bulbs or that a bad brake light switch could cause this...both ideas fucking dumb, IMO.

Now I gotta convince the damn thing to behave when I go to sequential LED turnsignals.

[The Barvarian]

Great pointer!!

[willybustaE30]

mine lights up when i turn the key on, then when i tap the brakes it goes off.
mine is related to the cruise control circuit that i disconnected.
brakes & cruise control were on the same circuit.
hope that helps as well.

[StereoInstaller1]

mine lights up when i turn the key on, then when i tap the brakes it goes off.

That is how it is SUPPOSED to operate...the other guy was having a different issue, being that it would tell him he had a bulb out when he was driving, and all bulbs were good.

[87Blue325iC]

Umm folks ....this is what it is supposed to do! Start the car and the check panel brake red light is on and the dash "check" light is flashing - tap the brakes and it stops. That is how the car is designed to work. If you tap the brakes and it doesn't go away, THEN you have a problem (follow Luke's instructions above).

[Garageaholic]

mine lights up when i turn the key on, then when i tap the brakes it goes off.
mine is related to the cruise control circuit that i disconnected.
brakes & cruise control were on the same circuit.
hope that helps as well.

Willybusta... please elaborate.

[george graves]

I'm going to build this just for Luke's e30:

http://www.youtube.com/watch?v=K6sZg3iL5EY

[einstein57]

those are sweet

[E30 Cabrio]

The 3rd brake light has a small circuit board that often fails, even though all your brake lights will work, it will still light up the check panel if this circuit board goes out.

Had it happen on both my old 86 es and my current 88 ic

You can either replace the PC board, or you can just bypass it, but if you decide to bypass it, your check panel won't light up if the 3rd brake light goes out.

[Jon325i]

Great write up Luke - I'm going to have to look into this for my car. I had the same issue for a while and it started to bug the eff outta me. So I did what any sensible cheap bastard would do.....unplugged the check panel :nice:

What about the switch at the brake pedal? I always thought this could be a problem too.

Jon